Working 9 to 5, not the way to make an academic living: observational analysis of manuscript and peer review submissions over time.

objectiveTo determine whether researchers are submitting manuscripts and peer reviews to BMJ journals out of hours and whether this has changed over time.

designObservational study of research manuscripts and peer reviews submitted between 2012 and 2019 for which an author's address could be geocoded.

settingOnline BMJ submission systems for two large general medical journals.

main outcome measuresManuscript and peer review submissions on weekends, on national holidays, and by hour of day (to determine early mornings and late nights). Logistic regression was used to estimate the probability of manuscript and peer review submissions on weekends or holidays.

resultsThe analyses included more than 49 000 manuscript submissions and 76 000 peer reviews. Little change over time was seen in the average probability of manuscript or peer review submissions occurring on weekends or holidays. The levels of out of hours work were high, with average probabilities of 0.14 to 0.18 for work on the weekends and 0.08 to 0.13 for work on holidays compared with days in the same week. Clear and consistent differences were seen between countries. Chinese researchers most often worked at weekends and at midnight, whereas researchers in Scandinavian countries were among the most likely to submit during the week and the middle of the day.

conclusionThe differences between countries that are persistent over time show that a "culture of overwork" is a literal thing, not just a figure of speech.